Nu forstår jeg ..destilleret vand på køleren .. (08-08-2012 08:34:00)
Lars Rindom Jensen #8410, reg. øsj
Jeg har aldrig helt forstået hvorfor det er en god ide at bruge destilleret vand på køleren .. og fandt så dette indlæg (andetsteds :o)
....electrolysis. This occurs when stray currents find their way, via the cooling system and the coolant , to earth.
I am aware of two ways to minimise electrolysis . Fistly ensure that the engine is properly earthed - clean up earth connections connections etc. Best of all fit another earth line , in addition to the standard one. This will ensure that stray voltages/ currents do not go via the cooling system to earth , but go direct via the earthing straps. A major cause of these currents is the heavy current flow every time the car is started. Check that some idiot hasnt connected a separate wire earthing the radiator , or worse still , using the radiator as an earth for spot lights - it has happened and is guaranteed disaster!
Secondly , when a fresh coolant mixture is made up every 2 years(50 % remember..) , use distilled or deionised water , and never top up with brackish water eg from a tap in the Karoo... Dont use softened water - it is dangerous and very different to deionised water. Use of distilled water will stop the coolant conducting electrical currents and thereby put a brake on electrolysis . It will also put a brake on galvanic electrolysis , which occurs when different metals are bathed in an ionic solution (ie in non distilled water) . Rainwater can be used in place of distilled water.
The wrong thing to do is to attempt to separately earth components such as the radiator and oil cooler - this will simply increase stray currents via these components and encourage electrolytic damage.
Taking these precautions has further benefits - easier starting , reduced tendency for head gaskets and heads to blow , water pump protection , radiator protection , reduced pressure in cooling system etc etc.